Shoppers who scour the high street for the best possible deals will still face the most expensive Christmas dinner in a decade.

The UK’s cheapest traditional festive spread will cost nearly 6% more than last year after the hot summer combined with uncertainty about Brexit to drive up the price of turkey, sprouts and Christmas pudding, according to the latest annual survey by Good Housekeeping magazine.

Even for those prepared to shop around for the cheapest options, the traditional meal will cost £3.11 per head, up from £2.94 last year and 25% higher than the £2.48 recorded in 2016, which was a 10-year low. Seven of the 10 supermarkets studied were more expensive than a year ago. The total price for a basket of 11 goods to feed a family of eight works out at £24.90.

Caroline Bloor, consumer affairs director at Good Housekeeping, said:“Consumers have had a lot of factors outside of their control affecting the cost of their Christmas dinner this year. The extreme weather at the beginning of the year alongside this summer’s heatwave has meant yields of crops were much lower than usual.

“This coupled with the weakened pound following the Brexit vote means that food prices increased this year across the board – and consumers are footing part of the bill.”

She added: “There’s still plenty of bargains to be had with competition at an all-time high between retailers – but consumers may need to be willing to shop around.”

The rise in the cost of a Christmas dinner is more than double the general rise in food inflation which was just 1.6% in November, compared with last year, according to the latest data from the British Retail Consortium as some traditional staples have been hit hard by supply shortages.

Of the 11 seasonal staples monitored annually by Good Housekeeping, Christmas pudding suffered the highest level of inflation – up 16%, as dried fruit and nut prices increased amid a global shortages.

Sprouts, turkey and Christmas cake will also cost significantly more than last year. The survey also covered stuffing mix, brandy butter and mince pies, which were all stable in price.

The price of potatoes was down year on year, according to the survey, despite harvest difficulties caused by the long dry summer, which the agricultural development board has said led to an 8% average price rise in stores.

Guy Poskitt, a root vegetable grower and member of the National Farmers Union’s horticultural board, said yields on carrots, potatoes and parsnips were all down by about 20% on average and production costs were up by about 30%. “In July traditional root vegetables were not growing. They are used to temperate climate and we had a nearly tropical climate.”

Heavy competition between the traditional supermarkets and the fast-growing discounters, which focus on advertising cheap vegetables in the days before Christmas, mean wholesale cost rises are not being passed on to shoppers in many cases.

“Core foods like vegetables and potatoes are fiercely competitive within the industry and so retailers are more likely to hold off on price rises in those areas,” said Richard Lim, chief executive of consultancy Retail Economics.

“The food market is going through enormous changes and most of that is driven by the discounters, who have doubled their market share in the last seven years. All of that will be coming through in the mix this Christmas.”